Tag Archives: Caleb Cox

Charged up t-shirts

There’s been a lot of talk about using t-shirts and other clothing to recharge telephones and other electronic devices but until now everything has been confined to the lab (as per my January 22, 2010 posting [scroll down about1/3 of the way] and my Feb. 15, 2010 posting). The latest edition of the Glastonbury Music Festival in the UK saw the introduction of Sound Charge, a t-shirt that harvests energy from ambient sound to recharge mobile phone batteries.

Here’s how Orange, the telecommunications company behind the Glastonbury experiment did it (from the Orange June 20, 2011 news release,

Following months of planning and development, the prototype, named the Orange ‘Sound Charge’ has been produced in conjunction with renewable energy experts at GotWind. The eco charging device uses an existing technology in a revolutionary way; by reversing the use of a product called Piezoelectric film, allowing people to charge their mobile phones whilst enjoying their favourite headline act at Glastonbury.

Usually found in modern hi-fi speakers, an A4 panel of the modified film is housed inside a t-shirt which then acts much like an oversized microphone by ‘absorbing’ invisible sound pressure waves. These sound waves are converted via the compression of interlaced quartz crystals into an electrical charge, which is fed into an integral reservoir battery that in turn charges most makes and models of mobile phone. As the ‘device’ is worn, a steady charge is able to be dispensed into the phone via a simple interchangeable lead which fits most handsets.

Thankfully given the nature of human sweat and dirt, the film is removable allowing the t-shirt to be cleaned and leaving the components unharmed.

Schematic for Sound Charge t-shirt prototype tested at 2011 Glastonbury Music Festival

As for how efficiently the t-shirts harvest energy and transform it to an electrical charge, there’s still work to be done. From the June 20, 2011 article by Caleb Cox for The Register,

Apparently over the course of a weekend, the T-shirt will only produce enough energy for roughly a single smartphone recharge, so it will probably follow in the footsteps of the wellies by remaining a non-commercial product.

This is not the first joint project between Orange and GotWind, last year they collaborated on ‘rechargeable wellies’ (wellies are rubber boots) for the Glastonbury Festival.